Q08HI2 · Q08HI2_PHOHO
- ProteinCytochrome c oxidase subunit 3
- GeneCOIII
- StatusUniProtKB unreviewed (TrEMBL)
- Amino acids261 (go to sequence)
- Protein existenceInferred from homology
- Annotation score2/5
Function
function
Component of the cytochrome c oxidase, the last enzyme in the mitochondrial electron transport chain which drives oxidative phosphorylation. The respiratory chain contains 3 multisubunit complexes succinate dehydrogenase (complex II, CII), ubiquinol-cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III, CIII) and cytochrome c oxidase (complex IV, CIV), that cooperate to transfer electrons derived from NADH and succinate to molecular oxygen, creating an electrochemical gradient over the inner membrane that drives transmembrane transport and the ATP synthase. Cytochrome c oxidase is the component of the respiratory chain that catalyzes the reduction of oxygen to water. Electrons originating from reduced cytochrome c in the intermembrane space (IMS) are transferred via the dinuclear copper A center (CU(A)) of subunit 2 and heme A of subunit 1 to the active site in subunit 1, a binuclear center (BNC) formed by heme A3 and copper B (CU(B)). The BNC reduces molecular oxygen to 2 water molecules using 4 electrons from cytochrome c in the IMS and 4 protons from the mitochondrial matrix.
Catalytic activity
- 4 Fe(II)-[cytochrome c] + O2 + 8 H+(in) = 4 Fe(III)-[cytochrome c] + 2 H2O + 4 H+(out)This reaction proceeds in the forward direction.
4 RHEA-COMP:10350 + CHEBI:15379 + 8 H+ (in)CHEBI:15378= 4 RHEA-COMP:14399 + 2 CHEBI:15377 + 4 H+ (out)CHEBI:15378
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | membrane | |
Cellular Component | mitochondrion | |
Molecular Function | cytochrome-c oxidase activity | |
Biological Process | mitochondrial electron transport, cytochrome c to oxygen |
Keywords
- Molecular function
Names & Taxonomy
Protein names
- Recommended nameCytochrome c oxidase subunit 3
Gene names
Encoded on
- Mitochondrion
Organism names
- Strain
- Taxonomic lineageEukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Laurasiatheria > Carnivora > Caniformia > Pinnipedia > Otariidae > Phocarctos
Accessions
- Primary accessionQ08HI2
Subcellular Location
UniProt Annotation
GO Annotation
Membrane ; Multi-pass membrane protein
Features
Showing features for transmembrane.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Transmembrane | 16-34 | Helical | ||||
Sequence: WPLTGALSALLMTSGLIMW | ||||||
Transmembrane | 40-58 | Helical | ||||
Sequence: IHLLLLGLMTNTLTMYQWW | ||||||
Transmembrane | 79-102 | Helical | ||||
Sequence: LRYGMILFIVSEVFFFAGFFWAFY | ||||||
Transmembrane | 159-177 | Helical | ||||
Sequence: MLQALFITILLGLYFTLLQ | ||||||
Transmembrane | 197-220 | Helical | ||||
Sequence: FFMATGFHGLHVIIGSTFLTVCFL | ||||||
Transmembrane | 240-260 | Helical | ||||
Sequence: WYWHFVDVVWLFLYVSIYWWG |
Keywords
- Cellular component
Structure
Family & Domains
Features
Showing features for domain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Domain | 4-261 | Heme-copper oxidase subunit III family profile | ||||
Sequence: QTHAYHMVNPSPWPLTGALSALLMTSGLIMWFHFNSIHLLLLGLMTNTLTMYQWWRDIVRESTFQGHHTPTVQKGLRYGMILFIVSEVFFFAGFFWAFYHSSLAPTPELGGCWPPAGITPLNPLEVPLLNTSVLLASGVSITWAHHSLMEGDRKHMLQALFITILLGLYFTLLQASEYYETPFTISDGVYGSTFFMATGFHGLHVIIGSTFLTVCFLRQLKFHFTSNHHFGFEAAAWYWHFVDVVWLFLYVSIYWWGS |
Sequence similarities
Belongs to the cytochrome c oxidase subunit 3 family.
Keywords
- Domain
Family and domain databases
Sequence
- Sequence statusFragment
- Length261
- Mass (Da)29,941
- Last updated2006-10-31 v1
- ChecksumAC6BD63048F01C80
Features
Showing features for non-terminal residue.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Non-terminal residue | 261 | |||||
Sequence: S |
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
KX388143 EMBL· GenBank· DDBJ | ANN02974.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
AM181019 EMBL· GenBank· DDBJ | CAJ56916.1 EMBL· GenBank· DDBJ | Genomic DNA |